// Copyright (c) 1998-2009 Nokia Corporation and/or its subsidiary(-ies).

// All rights reserved.

// This component and the accompanying materials are made available

// under the terms of "Eclipse Public License v1.0"

// which accompanies this distribution, and is available

// at the URL "http://www.eclipse.org/legal/epl-v10.html".

//

// Initial Contributors:

// Nokia Corporation - initial contribution.

//

// Contributors:

//

// Description:

// PASV command answer parser

// Author:	Philippe Gabriel

// RFC 959 defines the syntax for answer to the PASV command

// We must parse an IP+Port number (decimal, big endian)

// (ip1,ip2,ip3,ip4,ip5,port1,port2)

// We parse these regular expressions using an FSM

// Use:

// TFtpPASVAnswerParser::Reset 

// to Reset the parser before we begin to parse a new answer

// TFtpPASVAnswerParser::Parse 

// to parse an answer

// returns:

// TRUE: we parsed an answer (answer might be correct or inccorect)

// FALSE: An answer has not been completely parsed yet

// TFtpPASVAnswerParser::Fetch 

// Fetch an answer

// returns:

// TRUE: We got a valid answer

// FALSE: The answer we got had an invalid syntax

// 

//

/**

 @file PASVANS.CPP

 @internalComponent

*/

#include "DEBUG.H"

#include "PASVANS.H"

#include <e32base.h>

#include <e32test.h>

#include <in_sock.h>

//

// Definitions

//

TBool TFtpPASVAnswerParser::Fetch(TInetAddr& aFTPServerAddress)

	{

	__ASSERT_DEBUG((iState == ESuccess) || (iState == EFailed), User::Panic(_L("TFtpPASVAnswerParser::Fetch incorrect state"), 0));

	if(iState != ESuccess)

		return FALSE;

	aFTPServerAddress = iFTPServerAddress;

	return TRUE;

	}

void	TFtpPASVAnswerParser::Reset(void)

	{

	iState = EIdle;	

	iFTPServerAddress.SetFamily(KAFUnspec);

	}

TBool	TFtpPASVAnswerParser::Parse(const TDesC8& aBuffer, const TInetAddr& aAddr)

	{

	if (aAddr.Family() == KAfInet)

		return ParsePASV(aBuffer);

	else

		{

		__ASSERT_DEBUG(aAddr.Family() == KAfInet6, User::Panic(_L("TFtpPASVAnswerParser"), 0));

		iFTPServerAddress.SetAddress(aAddr.Ip6Address());

		return ParseEPSV(aBuffer);

		}

	}

TBool TFtpPASVAnswerParser::ParsePASV(const TDesC8& aBuffer)

	{

	const TUint8*	c;

	TInt			bufLen;

	TUint		aIPAndPort[6];

	if ((iState == ESuccess) || (iState == EFailed))

		// Already parsed an answer

		return TRUE;

	for (c= aBuffer.Ptr(),bufLen = aBuffer.Length();(bufLen>0);bufLen--,c++)

		{

		switch (iState)

			{

			case EIdle:

				if (*c=='(')

					{

					/* We fetched a (, begin parsing*/

					iNumberCounter=0;

					iState++;

					}

				break;

			case EBeginParse:

				if ((*c>='0') && (*c<='9'))

					{

					iDigit.Zero();

					iDigit.Append(*c);

					iState++;

					}

				break;

			case EParsing:

				if ((*c>='0') && (*c<='9'))

					if(iDigit.Length() == 3)

						{

						// We're stuffed, we got more than 3 digits

						iState = EFailed;

						return TRUE;

						}

					else

						{

						iDigit.Append(*c);

						}

				else // We should have a , or a ) I accept everything

					{

					//[1] Translate the last number that we parsed

					TUint	tempValue;

					TLex input(iDigit);

					input.Val(tempValue,EDecimal);

					if(tempValue>255)

						{

						// If Value out of bound, we're stuffed

						// Error bail out

						iState = EFailed;

						return TRUE;

						}

					aIPAndPort[iNumberCounter++] = tempValue;

					// [2] Are we waiting for more numbers?

					if(iNumberCounter == 6)

						{

						// OKay We've finished

						iFTPServerAddress.SetAddress(INET_ADDR(aIPAndPort[0],aIPAndPort[1],aIPAndPort[2],aIPAndPort[3]));

						iFTPServerAddress.SetPort(aIPAndPort[4]<<8 | aIPAndPort[5]);

						iState = ESuccess;

						return TRUE;

						}

					else

						// Fetch next number

						iState = EBeginParse;

					}

				break;

			default:

				break;

			}

		}

	return FALSE;

	}

TBool TFtpPASVAnswerParser::ParseEPSV(const TDesC8& aBuffer)

	{

	TInt			bufLen = aBuffer.Length();

	TUint           port = 0;

	if ((iState == ESuccess) || (iState == EFailed))

		// Already parsed an answer

		return ETrue;

	for (const TUint8* c = aBuffer.Ptr();bufLen>0;bufLen--,c++)

		{

		switch (iState)

			{

			case EIdle:

				if (*c=='(')

					{

					/* We fetched a (, begin parsing*/

					iState = EBeginParse;

					}

				break;

			case EBeginParse:

				if (TChar(*c).IsDigit())

					{

					port = *c - '0';

					iState = EParsing;

					}

				break;

			case EParsing:

				if (TChar(*c).IsDigit())

					{

					port = port*10 + (*c - '0');

					}

				else // We should have a "|", end the parsing

					{

					if(port>(1<<16) || *c != '|')

						{

						// If Value out of bound or  the last character is not a '|' 

						// then the parsing failed

						iState = EFailed;

						return ETrue;

						}

					iFTPServerAddress.SetPort(port);

					iState = ESuccess;

					return ETrue;

					}

				break;

			default:

				break;

			}

		}

	return EFalse;

	}